In this paper, with the heatwave during July 20-28, 2017 in Jiangsu Province as the background, a research was conducted on the influence of high-albedo walls, roads and roofs to urban heat and human health through coupling of WRF v3.9.1 mode and BEP/BEM scheme of multi-story urban canopy model. Results suggest: (1) compared with the ordinary cement calculation instance (CTR), the taller and denser the buildings in cities, the more significant the temperature reduction. The average temperature reduction at a height of 2 m in high-albedo wall calculation instance (WALL), high-albedo road calculation instance (ROAD), high-albedo roof calculation instance (ROOF) and all high-albedo surface (ALL) is 0.14, 0.44, 0.75 and 1.54 ℃ respectively at daytime (07∶00 BST-19∶00 BST) in financial districts; and 0.98, 1.06, 1.53 and 2.71 ℃ at maximum respectively. Meanwhile, the calculation instances of WALL, ROAD, ROOF and ALL will bring an average temperature reduction by 0.14, 0.43, 0.64 and 1.26 ℃ respectively in day time in the whole urban area. (2) While the adoption of high-albedo surface materials alleviates heat to some extent, there are also certain influences to human's comfort and death rate. During a heatwave, compared with CTR calculation instance, at 13∶00 BST, ALL calculation instance lowers the Temperature Humidity Index (THI) by 0.93, 1.11 and 1.48 in low-density residential districts, high-density residential districts and financial districts respectively; the heat-related emergency treatment rate and death rate is reduced by 2.9%, 4.8%, 9.5% and 3.4%, 5.6%, 10.9% at maximum respectively.